1 #!/usr/bin/env python3
2 # Copyright (c) 2015-present The Bitcoin Core developers
3 # Distributed under the MIT software license, see the accompanying
4 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
5 """Test BIP65 (CHECKLOCKTIMEVERIFY).
6 7 Test that the CHECKLOCKTIMEVERIFY soft-fork activates.
8 """
9 10 from test_framework.blocktools import (
11 TIME_GENESIS_BLOCK,
12 create_block,
13 )
14 from test_framework.messages import (
15 CTransaction,
16 SEQUENCE_FINAL,
17 msg_block,
18 )
19 from test_framework.p2p import P2PInterface
20 from test_framework.script import (
21 CScript,
22 CScriptNum,
23 OP_1NEGATE,
24 OP_CHECKLOCKTIMEVERIFY,
25 OP_DROP,
26 )
27 from test_framework.test_framework import BitcoinTestFramework
28 from test_framework.util import assert_equal
29 from test_framework.wallet import (
30 MiniWallet,
31 MiniWalletMode,
32 )
33 34 35 # Helper function to modify a transaction by
36 # 1) prepending a given script to the scriptSig of vin 0 and
37 # 2) (optionally) modify the nSequence of vin 0 and the tx's nLockTime
38 def cltv_modify_tx(tx, prepend_scriptsig, nsequence=None, nlocktime=None):
39 assert_equal(len(tx.vin), 1)
40 if nsequence is not None:
41 tx.vin[0].nSequence = nsequence
42 tx.nLockTime = nlocktime
43 44 tx.vin[0].scriptSig = CScript(prepend_scriptsig + list(CScript(tx.vin[0].scriptSig)))
45 46 47 def cltv_invalidate(tx, failure_reason):
48 # Modify the signature in vin 0 and nSequence/nLockTime of the tx to fail CLTV
49 #
50 # According to BIP65, OP_CHECKLOCKTIMEVERIFY can fail due the following reasons:
51 # 1) the stack is empty
52 # 2) the top item on the stack is less than 0
53 # 3) the lock-time type (height vs. timestamp) of the top stack item and the
54 # nLockTime field are not the same
55 # 4) the top stack item is greater than the transaction's nLockTime field
56 # 5) the nSequence field of the txin is 0xffffffff (SEQUENCE_FINAL)
57 assert failure_reason in range(5)
58 scheme = [
59 # | Script to prepend to scriptSig | nSequence | nLockTime |
60 # +-------------------------------------------------+------------+--------------+
61 [[OP_CHECKLOCKTIMEVERIFY], None, None],
62 [[OP_1NEGATE, OP_CHECKLOCKTIMEVERIFY, OP_DROP], None, None],
63 [[CScriptNum(100), OP_CHECKLOCKTIMEVERIFY, OP_DROP], 0, TIME_GENESIS_BLOCK],
64 [[CScriptNum(100), OP_CHECKLOCKTIMEVERIFY, OP_DROP], 0, 50],
65 [[CScriptNum(50), OP_CHECKLOCKTIMEVERIFY, OP_DROP], SEQUENCE_FINAL, 50],
66 ][failure_reason]
67 68 cltv_modify_tx(tx, prepend_scriptsig=scheme[0], nsequence=scheme[1], nlocktime=scheme[2])
69 70 71 def cltv_validate(tx, height):
72 # Modify the signature in vin 0 and nSequence/nLockTime of the tx to pass CLTV
73 scheme = [[CScriptNum(height), OP_CHECKLOCKTIMEVERIFY, OP_DROP], 0, height]
74 75 cltv_modify_tx(tx, prepend_scriptsig=scheme[0], nsequence=scheme[1], nlocktime=scheme[2])
76 77 78 CLTV_HEIGHT = 111
79 80 81 class BIP65Test(BitcoinTestFramework):
82 def set_test_params(self):
83 self.num_nodes = 1
84 # whitelist peers to speed up tx relay / mempool sync
85 self.noban_tx_relay = True
86 self.extra_args = [[
87 f'-testactivationheight=cltv@{CLTV_HEIGHT}',
88 '-acceptnonstdtxn=1', # cltv_invalidate is nonstandard
89 ]]
90 self.setup_clean_chain = True
91 self.rpc_timeout = 480
92 93 def test_cltv_info(self, *, is_active):
94 assert_equal(self.nodes[0].getdeploymentinfo()['deployments']['bip65'], {
95 "active": is_active,
96 "height": CLTV_HEIGHT,
97 "type": "buried",
98 },
99 )
100 101 def run_test(self):
102 peer = self.nodes[0].add_p2p_connection(P2PInterface())
103 wallet = MiniWallet(self.nodes[0], mode=MiniWalletMode.RAW_OP_TRUE)
104 105 self.test_cltv_info(is_active=False)
106 107 self.log.info("Mining %d blocks", CLTV_HEIGHT - 2)
108 self.generate(wallet, 10)
109 self.generate(self.nodes[0], CLTV_HEIGHT - 2 - 10)
110 assert_equal(self.nodes[0].getblockcount(), CLTV_HEIGHT - 2)
111 112 self.log.info("Test that invalid-according-to-CLTV transactions can still appear in a block")
113 114 # create one invalid tx per CLTV failure reason (5 in total) and collect them
115 invalid_cltv_txs = []
116 for i in range(5):
117 spendtx = wallet.create_self_transfer()['tx']
118 cltv_invalidate(spendtx, i)
119 invalid_cltv_txs.append(spendtx)
120 121 tip = self.nodes[0].getbestblockhash()
122 block_time = self.nodes[0].getblockheader(tip)['mediantime'] + 1
123 block = create_block(int(tip, 16), height=CLTV_HEIGHT - 1, ntime=block_time, version=3, txlist=invalid_cltv_txs)
124 block.solve()
125 126 self.test_cltv_info(is_active=False) # Not active as of current tip and next block does not need to obey rules
127 peer.send_and_ping(msg_block(block))
128 self.test_cltv_info(is_active=True) # Not active as of current tip, but next block must obey rules
129 assert_equal(self.nodes[0].getbestblockhash(), block.hash_hex)
130 131 self.log.info("Test that blocks must now be at least version 4")
132 tip = block.hash_int
133 block_time += 1
134 block = create_block(tip, height=CLTV_HEIGHT, ntime=block_time, version=3)
135 block.solve()
136 137 with self.nodes[0].assert_debug_log(expected_msgs=[f'{block.hash_hex}, bad-version(0x00000003)']):
138 peer.send_and_ping(msg_block(block))
139 assert_equal(int(self.nodes[0].getbestblockhash(), 16), tip)
140 peer.sync_with_ping()
141 142 self.log.info("Test that invalid-according-to-CLTV transactions cannot appear in a block")
143 block.nVersion = 4
144 block.vtx.append(CTransaction()) # dummy tx after coinbase that will be replaced later
145 146 # create and test one invalid tx per CLTV failure reason (5 in total)
147 for i in range(5):
148 spendtx = wallet.create_self_transfer()['tx']
149 assert_equal(len(spendtx.vin), 1)
150 coin = spendtx.vin[0]
151 coin_txid = format(coin.prevout.hash, '064x')
152 coin_vout = coin.prevout.n
153 cltv_invalidate(spendtx, i)
154 155 blk_rej = "block-script-verify-flag-failed"
156 tx_rej = "mempool-script-verify-flag-failed"
157 expected_cltv_reject_reason = [
158 " (Operation not valid with the current stack size)",
159 " (Negative locktime)",
160 " (Locktime requirement not satisfied)",
161 " (Locktime requirement not satisfied)",
162 " (Locktime requirement not satisfied)",
163 ][i]
164 # First we show that this tx is valid except for CLTV by getting it
165 # rejected from the mempool for exactly that reason.
166 spendtx_txid = spendtx.txid_hex
167 spendtx_wtxid = spendtx.wtxid_hex
168 assert_equal(
169 [{
170 'txid': spendtx_txid,
171 'wtxid': spendtx_wtxid,
172 'allowed': False,
173 'reject-reason': tx_rej + expected_cltv_reject_reason,
174 'reject-details': tx_rej + expected_cltv_reject_reason + f", input 0 of {spendtx_txid} (wtxid {spendtx_wtxid}), spending {coin_txid}:{coin_vout}"
175 }],
176 self.nodes[0].testmempoolaccept(rawtxs=[spendtx.serialize().hex()], maxfeerate=0),
177 )
178 179 # Now we verify that a block with this transaction is also invalid.
180 block.vtx[1] = spendtx
181 block.hashMerkleRoot = block.calc_merkle_root()
182 block.solve()
183 184 with self.nodes[0].assert_debug_log(expected_msgs=[f'Block validation error: {blk_rej + expected_cltv_reject_reason}']):
185 peer.send_and_ping(msg_block(block))
186 assert_equal(int(self.nodes[0].getbestblockhash(), 16), tip)
187 peer.sync_with_ping()
188 189 self.log.info("Test that a version 4 block with a valid-according-to-CLTV transaction is accepted")
190 cltv_validate(spendtx, CLTV_HEIGHT - 1)
191 192 block.vtx.pop(1)
193 block.vtx.append(spendtx)
194 block.hashMerkleRoot = block.calc_merkle_root()
195 block.solve()
196 197 self.test_cltv_info(is_active=True) # Not active as of current tip, but next block must obey rules
198 peer.send_and_ping(msg_block(block))
199 self.test_cltv_info(is_active=True) # Active as of current tip
200 assert_equal(self.nodes[0].getbestblockhash(), block.hash_hex)
201 202 203 if __name__ == '__main__':
204 BIP65Test(__file__).main()
205